resumo
The use of macroalgae, microalgae and cyanobacteria for metal sorption has been widely reported. Still, there are no studies allowing a direct comparison of the performance of these biomasses, especially while evaluating metal competition. The simultaneous sorption of Co2+, Cu2+, Ni2+ and Zn2+ present in a multi-elemental solution by six macroalgae, two microalgae and three cyanobacteria was evaluated. Brown macroalgae were shown to be the most promising biosorbent, with Undaria pinnatifida having a total metal sorption capacity of 0.6 mmol g(-1). Overall, macroalgae performed better than microalgae, followed by cyanobacteria. Carboxyl groups were identified as being the main functional groups involved in metal sorption, and all biomass samples were found to be selective to Cu2+. This was linked not only to its higher complexation constant value with relevant functional groups when compared to the remaining metals, but also the Irving-Williams series. The release of K+ and Ca2+ to the aqueous solution during the metal sorption was followed. The obtained results suggest they are readily exchanged with metals in the solution, indicating the occurrence of an ion-exchange mechanism in metal sorption by most biomass. Red macroalgae are an exception to the reported trends, suggesting that their metal sorption mechanism may differ from the other biomass types.
palavras-chave
BIOSORPTION; BIOREMEDIATION; EFFLUENTS; CADMIUM; NICKEL; LEAD
categoria
Environmental Sciences & Ecology
autores
Carreira, ARF; Veloso, T; Macário, IPE; Pereira, JL; Ventura, SPM; Passos, H; Coutinho, JAP
nossos autores
Helena Isabel Sousa Passos
Investigador Júnior
Sónia Patrícia Marques Ventura
Professor AuxiliarProjectos
CICECO - Aveiro Institute of Materials (UIDB/50011/2020)
CICECO - Aveiro Institute of Materials (UIDP/50011/2020)
Associated Laboratory CICECO-Aveiro Institute of Materials (LA/P/0006/2020)
Collaboratory for Emerging Technologies, CoLab (EMERGING TECHNOLOGIES)
Valorização de pigmentos de cianobactérias pela aplicação do conceito de biorefinaria. (REFINECYANO)
agradecimentos
This work was developed within the scope of the project CICECO-Aveiro Institute of Materials, UIDB/50011/2020, UIDP/50011/2020 & LA/P/0006/2020, financed by national funds through the FCT/MEC (PIDDAC) and CESAM (UIDP/50017/2020+UIDB/50017/2020+LA/P/0094/2020) . Ana R. F. Carreira, Telma Veloso and Ine?s P. E. Macario acknowledge FCT for the Ph.D. grants SFRH/BD/143612/2019, SFRH/BD/147346/2019 and SFRH/BD/123850/2016, respectively. Helena Passos acknowledges FCT - Fundacao para a Ciencia e a Tecnologia, I.P. for the researcher contract CEECIND/00831/2017 under the Scientific Employment Stimulus-Individual Call 2017. The authors acknowledge the financial support of FCT regarding the project REFINECYANO (PTDC/BTA-BTA/30914/2017) . The authors would like to thank Nic-olas Schaeffer (CICECO) for fruitful discussions and ALGAplus, Lda. for providing algal samples.